The man sits on the chair as if it is a horse, telling of the family values he espouses and performing a seated dance with the machismo of a cowboy. A 70-year-old woman who has lived through testing times spins across the stage like a top. A man skips, so light on his feet that he nimbly dodges the rope that might trip him up - just like his own father who cornered him in an alley when he discovered his son was gay.

The dance-theatre company DV8 and its artistic director, Lloyd Newson, have always been well ahead of the game. Now, just at a point when others are catching up, Newson reinvents the rules with this piece, led by verbatim theatre based on 85 interviews with those who have experienced homophobia, have strict religious beliefs, or who are juggling their sexuality with their faith.

Newson is drawing on the fact that 85 countries around the world still criminalise same-sex relationships, and in seven, the death penalty exists for consensual sexual acts between adults of the same gender. This homophobia is frequently linked to religious beliefs, particularly the more extreme ends of Islam and Christianity. But the most shocking thing about To Be Straight With You is that many of the personal stories it tells belong to people living in secular Britain - where the veneer of tolerance turns out to be a thin one, and the respect accorded to some minorities is not always reciprocated when it comes to homosexuality. It is a situation that has led Peter Tatchell to suggest that "in the name of 'unity' against Islamopobia and racism, much of the left tolerates misogyny and homophobia in minority communities".

To Be Straight With You is a hard-hitting and passionate 80 minutes that expresses what is often left unsaid. There are problems. For the first 10 minutes, the dialogue is hard to hear. It is also visually over-busy; the monologue form is limiting; and, like a great deal of verbatim theatre, it preaches to the already converted.

But when it starts really getting physical, the gloves are off, both politically and creatively. I loved the immigration lawyer whose duet illustrates the push and pull of the law. Like the two married men having an affair, you will not be able to resist the music, or this brave, life-affirming show.

· At the Sherman Theatre, Cardiff (029 2064 6900), on April 24 and 25. Then touring.